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<p class='vspace'></p><h2>Wire Library</h2>
<p>This library allows you to communicate with <span class='wikiword'>I2C</span> / TWI devices.  On the Arduino, SDA (data line) is on analog input pin 4, and SCL (clock line) is on analog input pin 5.
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<p class='vspace'></p><h4>Functions</h4>
<ul><li><a class='wikilink' href='WireBegin.html'>begin</a>()
</li><li><a class='wikilink' href='WireBegin.html'>begin</a>(address)
</li><li><a class='wikilink' href='WireRequestFrom.html'>requestFrom</a>(address, count)
</li><li><a class='wikilink' href='WireBeginTransmission.html'>beginTransmission</a>(address)
</li><li><a class='wikilink' href='WireEndTransmission.html'>endTransmission</a>()
</li><li><a class='wikilink' href='WireSend.html'>send</a>()
</li><li>byte <a class='wikilink' href='WireAvailable.html'>available</a>()
</li><li>byte <a class='wikilink' href='WireReceive.html'>receive</a>()
</li><li><a class='wikilink' href='WireOnReceive.html'>onReceive</a>(handler)
</li><li><a class='wikilink' href='WireOnRequest.html'>onRequest</a>(handler)
</li></ul><p class='vspace'></p><h4>Note</h4>
<p>There are both 7- and 8-bit versions of <span class='wikiword'>I2C</span> addresses.  7 bits identify the device, and the eighth bit determines if it's being written to or read from.  The Wire library uses 7 bit addresses throughout.  If you have a datasheet or sample code that uses 8 bit address, you'll want to drop the low bit (i.e. shift the value one bit to the right), yielding an address between 0 and 127.
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<p class='vspace'></p><p><em>Corrections, suggestions, and new documentation should be posted to the <a class='urllink' href='http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?board=swbugs' rel='nofollow'>Forum</a>.</em>
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<p class='vspace'></p><p>The text of the Arduino reference is licensed under a
<a class='urllink' href='http://creativecommons.org/licenses/by-sa/3.0/' rel='nofollow'>Creative Commons Attribution-ShareAlike 3.0 License</a>.  Code samples in the reference are released into the public domain.
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